Coolant Leak From Heater Core on Mitsubishi Diamante

A coolant leak may develop from the heater core, requiring replacement of the heater core.

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Average mileage: 87,868 (25,986–187,000)
7 model years affected: 1998, 1999, 2000, 2001, more2002, 2003, 2004
29 people reported this problem
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Viewing 1 - 18 of 18 problem details
2003 Mitsubishi Diamante 70,100 mi,
The problem is the heater core and I want to know if it has been on recall. 2003 Mitsibushi Galant
2000 Mitsubishi Diamante 45,000 mi,
Replaced radiator, but slow coolant leak reoccurred after few months. Foggy front windows, smell of coolant, empty radiator, slight engine overheating. Returned to same mech who replaced radiator, they pressure test and leak check but could not find anything obvious. Finally they diagnosed heater coil leak inside dash. Expensive job to fix, at least $1K. Debating worth it on 12+ year old car, which is otherwise in fantastic driving condition.
2003 Mitsubishi Diamante 80,000 mi,
I noticed a sweet smell coming from heater, call dealer and he said that it was the heater core. He also said that it's a problem in most Diamantes. I ask if there was a recall, told me no :( I put stop leak in the radiator for now
1999 Mitsubishi Diamante 99,673 mi,
i was driving the car after cleaning it and the floor felt wet so i pulled the mat up and it was damp so i pulled the plastic off under the glove box and felt a lot of condonsation on the white box around the heater core
lots of film on windshield hard to see and hard to get off. Hard to breath with windows closed. Any Recalls on this problem? Very expensive to repair.
Heater core started leaking, started dripping inside the care as well onto the passenger side floor.
syrupy smell, foggy front window, soaked passenger carpet
2002 Mitsubishi Diamante 75,000 mi,
heater core had to be replaced
2003 Mitsubishi Diamante 54,000 mi,
Replaced Heater Core
2001 Mitsubishi Diamante 120,000 mi,
Coolant leak from heater coil. Defrost not defogging windshield.
2002 Mitsubishi Diamante 90,000 mi,
coolant leak from heater core. returned to dealer. at the time i had a extended warranty that covered the parts and service.
2003 Mitsubishi Diamante 25,986 mi,
We we're driving and front floor board got wet a went by and had no heat and the we changed the thermal thing and then we drove twenty miles and it over heated so bad that it killed the car now through all this my head was damage so they want 1900 hundred to do the heater core and water pump and to just take off the head ( knew head not include ) is this worth it like all this at once why what could of done this thank u if have read this but I have no clue so please give me some advice on getting cheap stuff to do this but not used and on another not would it be better to put a new engine in the car instead of fixing the water pump have all ready replaced radiator thank u Mrs Bird jessie
Leak around heater core causing windows to fog up
leaking water or right at the floor on the floor of the car inside
over heating in the heater core system an leakin like hell after travalling 5 km??
2003 Mitsubishi Diamante 130,000 mi,
03 MITSUB DIAM LS --IM HAVING PROBLEMS WITH MY DEFROST AND SMOKE COMING INTO THE VEHICLE FROM THE GLOVE COMPARTMENT AND VENTS. iT STARTED AS MIST NOW ITS FOGGING UP MY WINDOWS. IM HAVING TO CRACK MY PASSENGER WINDOW TO BREATH.
2001 Mitsubishi Diamante 58,000 mi,
smell of coolant and heating/air flow to lower compartment only blows cold air.
1998 Mitsubishi Diamante 187,000 mi,
i have the same problem with the heater coil, but mine went out and now it is time for replacement.